KINEMATIC ANALYSIS OF UNEVEN BAR DISMOUNTS IN THE 1994 WORLD GYMNASTICS CHAMPIONSHIP

Abstract

INTRODUCTION - Research related to dismounts has been largely concentrated on the horizontal bar (Park et al., 1994; Kerwinet al., 1993; Takei et al,. 1992). Although similarities between horizontal bar and uneven bar dismounts may exist, differences should also be expected due to (among other things) differences in the physical characteristics and design of the apparatuses. The purpose of this study was to kinematically analyze dismounts from the uneven bars and, when appropriate, to compare the result with existing data from horizontal bar dismounts. METHODS - Eight dismounts (six double layout and two double piked somersaults),recorded during the 1994 World Gymnastics Championships with 2 Panasonic videocameras operating at 50 Hz, were analyzed utilizing the Ariel Performance Analysis System(APAS). Three dimensional position data of 8 (ankles, hips, shoulders and wrists)to 10 (the above, plus knees and/or elbows)body points were digitally smoothed before being submitted to further analysis. RESULTS - Results showed mean shoulder and hip joint release angles of 144 and148 degrees, respectively. All gymnasts released the bar with the center of mass below bar level (Mean = -12.43 degrees),which was similar to data reported by Kerwin et al. (1 993) for triple somersault dismounts and Park et al. (1 994) for triple and double layout somersault dismounts. Center of mass horizontal release velocities(Mean = 1.33 mlsec) were similar to those reported by Park et al., 1994, Kerwinet al., 1993, and Takei et al,. 1992 for male gymnasts. However, vertical release velocities(Mean = 3.53 mlsec) and consequently maximum height above the bar (Mean = 0.28m), were substantially smaller that those reportedby Takei et al. and Park et al. CONCLUSION - Results indicate that although the general pattern for uneven bar dismounts is similar to the one for horizontal bar dismounts differences exist warranting that specific instructions be given to athletes. REFERENCES Park, S.S., & Prassas, S. (1 994). A comparative analysis of the triple backward somersault and the double backward somersault on the high bar. In A. Barabas & Gy.Fabian (Eds.) Biomechanics in Sports XI1(pp. 252-254). Hungarian University of Physical Education.Kerwin, D., Yeadon, M., & Harwood, M.(1993). High bar release in triple somersault dismounts. International Journal of Sport Biomechanics, 9, 279-286.Takei, Y., Nohara, H. & Kamimura, M.(1 992). Techniques used by elite gymnastsin the 1992 Olympic compulsory dismount from the horizontal bar. International Journalof Sport Biomechanics, 8, 207-232.